1. Field of the Invention
The present invention relates to a system for attenuating noise of an image signal, and more particularly, to a method of attenuating image-noise adaptively according to a degree of motion in an image signal, and an apparatus therefor. The present application is based on Korean Patent Application No. 2001-88225, filed Dec. 29, 2001, which is incorporated herein by reference.
2. Description of the Related Art
FIG. 1 is a view of a three-dimensional image signal. Referring to FIG. 1, a plurality of frames of an image signal are arranged in a temporal direction. Each frame has a spatial area with a vertical component and a horizontal component.
FIG. 2 is a block diagram of a conventional apparatus for attenuating image-noise. Referring to FIG. 2, a spatial noise attenuator 110 attenuates noise of an image signal in a spatial area using a low-pass filter. A temporal noise attenuator 120 attenuates noise of the image signal output from the spatial noise attenuator 110 in a temporal direction using the low-pass filter.
Here, the spatial noise attenuator 110 attenuates radio frequency components as well as noise components, which causes damage to the image signal and results in reduced noise attenuation as the degree of motion of the image signal increases.
Accordingly, as shown in FIG. 1, if the spatial noise attenuator 110 and the temporal noise attenuator 120 are connected to each other, the spatial noise attenuator 110 damages the image signal regardless of the degree of motion of the image signal.